In a roller mill with an air separator arranged immediately above it, it is known from EP-A-370 267 to provide a device by means of which fresh material for grinding is delivered to the rotating grinding table (with grinding rollers rolling on it). This delivery device is constructed like a material feed chute and is provided on its base which runs obliquely downwards with two air inlet channels through each of which an air stream can be delivered in such a way that proportions of fines can be separated out from the freshly delivered material for grinding and delivered to the air separator, as a result of which the crushing device is relieved of the proportions of fines which have been separated out and thus its crushing efficiency should be improved.
The object of the invention is to make further improvements in such a way that by relatively simple measures at least an additional increase in efficiency can be achieved in the crushing of material for grinding.